does work hardening differ with hotter loads?

[Tomekeuro85]

I have some remington .223 brass, Its on its 5th firing. Never been annealed.

I'm getting some random extreme flyers.


Might this be because of past load testing where I would load up rounds progressively hotter?

The light loads didnt work harden as much as the hotter ones.. then I mix them all back together and now I have neck tensions all over the place from what I loaded last, and hardness is all over the place as well, causing uneven release?

Does that sound logical/probable?

I noticed while seating the last batch of 100 that some bullets would seat easy and smooth, while other would seat hard and scrape the jacket. More side effects of varying hardness on the necks?

I'm getting a pretty consistent 1.8-2.2" group size at 300 with 52 smk and 24.3gr h322. Factory rem 700vls 1:12 twist

But then theres just one flyer anywhere from 1-3 inches away from the rest of the group. no flinch or any of that nonsense, brass is uniformed in every way except annealing, and the flyers vary in direction...


And side question. If I annealed the brass, and got a meplat uniformer, would this be a significant help to increase consistency?

Help? Thanks!

 

[vman]

Re: does work hardening differ with hotter loads?

Tom, you hit the nail on the head.

Work hardening will affect neck tension.

As to your side question, annealing the brass will help most deffinately.

Meplat uniformer, not so much. Unless you are an elite world class BR shooter, you wont notice the difference.

Meplat uniformity will become apparent when your shooting form is 100% and you wind calls are spot on every time.

 

[Tomekeuro85]

Re: does work hardening differ with hotter loads?

Thank you sir!

So you would agree that the reason for the extreme flyers is just the big difference in neck tension on those particular pieces of brass?

Ie, I double weigh my charges, brass is all uniform, smk's are pretty good quailty, benchrest primers, etc. I don't see any other reason that there would be one round that hits 3" higher than the rest. Except like I said during seating, some were extra loose, some were extra tight.

 

[Tomekeuro85]

Re: does work hardening differ with hotter loads?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: vman</div><div class="ubbcode-body"> Unless you are an elite world class BR shooter, you wont notice the difference. </div></div>


haha whats to say im not!?! Havent you ever heard of me???

lol

 

[Clark]

Re: does work hardening differ with hotter loads?

Work hardening if a function of how far and how many times the brass is stretched.

Per my experiments with 223, the 55kpsi SAAMI registered max average pressure is a long way from the max practical for long brass life of 75 kpsi.

That said, the amount of case length growth at high pressures is huge. Trimming would be needed every other sizing. And that is carefully only pushing the shoulder back .001" of change.

There is probably the possibility of a tighter body reamer to get around this, but the easiest way is with neck sizing. And only carefully fed actions can have super tight chambers anyway, to the answer is Lee collet neck dies.

 

[jeremybowlin]

Re: does work hardening differ with hotter loads?

I have a ruger m77 target in 220swift. if i do not anneal after two firings groups open up to 2 plus inches. If i anneal and prep my brass 100% every-time the groups goes back to under 1/2 inch. This rifle is very picky on neck tension being the same. So i do believe now that it can make a heck of a difference on neck tension.

 

[Fuzzball]

Re: does work hardening differ with hotter loads?

Work hardening is a function of how large the chamber neck is vs. how much the case necks get sized down. The chamber pressure, as such, has little to do with it.

 

[pawprint]

Re: does work hardening differ with hotter loads?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Fuzzball</div><div class="ubbcode-body">Work hardening is a function of how large the chamber neck is vs. how much the case necks get sized down. The chamber pressure, as such, has little to do with it. </div></div>
I agree. One other thing, the how true is the chamber, and how true are the dies.

 

[Tomekeuro85]

Re: does work hardening differ with hotter loads?

Thank you for the input. Very helpful.

I guess my question, however, was more along the lines of...

When brass work hardens, does it do so consistently? Meaning each piece of brass will harden just like the others? OR will the hardening be random between the various cases, and some might be harder than others?

 

[vman]

Re: does work hardening differ with hotter loads?

In theory it should be similar. There are more variables to this than just plain old work hardening.

- As mentioned, how tight is your chambers neck?
- How consistent are neck thicknesses.
- How consistent are the necks all together
- Is there a lot of run out?
- How good is the indian?

 

[Fuzzball]

Re: does work hardening differ with hotter loads?

IF cases were precisely the same in alloy and thickness in every area, they might be consistant enough to be predictable. They are not that precise, not even those in the same box.